This invention relates in general to mounting devices and apparatus which entail the assembly of two component parts. More particularly, this invention relates to rear-view mirror mounting apparatus wherein one part is bonded to the inside surface of the windshield and the cooperating part is attached to the back side of the rear-view mirror.
The mounting of rear-view mirrors into automobiles presents to designers an interesting combination of requirements. The component part which is bonded to the inside of the windshield needs to be fairly thin so that windshields can be efficiently stacked for shipment. Next, the connecting assembly between the windshield and the mirror needs to be adjustable in a conical sweep or zone in order for different drivers to focus the mirror to their particular viewing preferences. The mounting apparatus needs to be easily and positively assembled and thereafter remain secure for the life of the automobile. Finally, if there is a failure of the mirror or a need to replace the mirror, the component parts of the mounting apparatus need to be separable without significant difficulty and without causing damage to either the mirror or to the windshield.
The patents listed below disclose various attachment and mounting concepts, many of which involve two mating parts, wherein one part is configured to slidably receive the other part. However, none of these disclosed concepts anticipate nor render obvious the present invention.
______________________________________ Patent No. Patentee Issue Date ______________________________________ 240,843 Pontius 5/03/81 408,278 White 8/06/89 409,893 Wray 8/27/89 2,801,895 Gass 8/06/57 1,272,899 Berko 7/16/18 3,696,233 Pulsifer 10/03/72 4,019,298 Johnson, IV 4/26/77 3,367,616 Bausch et al. 2/06/68 4,225,258 Thompson 9/30/80 ______________________________________
Pontius discloses a fencepost construction wherein the lower portion of the fencepost is shaped as a partial four-sided pyramid. The base member for the fencepost has an opening with a compatible dovetail-like shape suitable to receive the part pyramid-shaped end of the post.
White discloses a concept for knock-down furniture wherein cylindrical dowel-like cross bars are configured with a conical end portion which fit within recessed keyhole-like depressions. The keyhole-like depressions are undercut along their lower portion so as to receive the conical end of the cross bars after these conical ends are inserted into the larger opening of the keyhole-like shape.
Wray discloses a lock joint for beams wherein the end of a beam is shaped with a dovetail protuberance and the portion into which the beam is locked is adapted to engage and rest on the beam and includes a dovetail socket open at the top. The dovetail socket tapers inwardly as it extends downwardly so as to provide a locking concept for the beams and thereby accepts tolerance variations within the dovetail socket and the dovetail end of the beam.
Gass discloses an interlocked joint construction for structures such as drawers and cabinets and includes a dovetail protuberance on a first member and a similarly shaped dovetailed receiving channel in the mating member. This particular construction concept is somewhat similar to the structure of the Wray patent with the exception that in Gass, the recessed and dovetail-shaped receiving channel is not tapered.
Berko discloses a bathroom fixture wherein an undercut channel receives a mating member, and although a dovetail attachment is illustrated in FIG. 2, this particular disclosure is only believed to be of limited relevancy to the present invention.
Pulsifer discloses an infant feeding device which includes a receptacle member and means for holding the receptacle member in proximity to the infant. The receptacle member includes an opening whereby the bottle can be introduced therein and a slotted end wall portion in which slot the neck portion of the bottle rests, the slot width being less than the diameter of the main body portion of the bottle. The coupling element attached to the bottle holder has a generally dovetail configuration and is somewhat uniform so as to approximate a four-sided pyramid. The coupling member includes a tapered receiving channel and functions similarly to a dovetail joint.
Johnson, IV discloses a dual-tapered dovetail-shaped mortise which is formed within a joist to receive a dual-tapered dovetail-shaped tenon extending from a beam. Laterally oriented cavities are disposed within opposite faces of the mortise to receive corresponding configured ridges formed integral with the mating tenon. The resulting frictional interlock between the mortise and the tenon, created by two forces acting in opposition to one another, rigidly secures the beam to the joist without play therebetween. The dovetail-shaped end of the beam is conventionally just that, but is tapered to correspond to the dovetail shape and taper of the receiving channel. The resulting frictional fit is established between the ridges and cavities and not necessarily between the dovetail end and the dovetail channel.
Bausch et al. discloses a support for rear-vision mirrors which is believed to describe a fairly standard and fairly typical construction within the automotive industry. A diecast metal base member is secured to the windshield and locked within this member is the stem end of a first ball. The ball is received within a cylindrical member and is spring loaded so as to exert a proper tension for adjustment of the mirror. The opposite end of the cylindrical member also includes a ball whose stem portion attaches to the back side of the mirror. The disadvantages with this construction concept are of course the plurality of pieces required in order to make the overall assembly, and the awkwardness of the sliding and pivoting motion between the cylindrical center member and the two ball ends. There is also a lack of durability and rigidity with this construction concept and the overall device of Bausch.
Thompson discloses a pivot mechanism concept which is believed to overcome several of the disadvantages with the Bausch et al. support apparatus for rear-vision mirrors. While the particular concepts set forth in this patent have widespread applicability, one application is in the automotive industry for mounting rear-vision mirrors. Nonetheless, there remain concerns with the mounting apparatus for such mirrors, namely an inexpensive and reliable way to secure the connection element to the windshield as well as to the mirror. These are the areas focused upon by the present invention.
Those designs which offer a dovetail-shaped, tapering channel, such as Wray, are believed preferred for quick and positive assembly of two mating parts. However, in these designs, the inserted dovetail shape and the shape of the receiving channel are such that there is no top-to-bottom clearance, just side clearance until such time as the taper closes in and wedges the two parts together. In this regard, it is instructive to note that the disclosed dovetail shapes each have a substantially flat base surface and the floor of each channel is also substantially flat. By this approach, there are only two points of force, these two points being on the sides. There are no force points longitudinally for the interference contact between the two parts which would tend to prevent the two parts from rocking and which would tend to prevent the inserted part from backing out of its mating engagement with the receiving part. Additionally, the dovetail inserts disclosed are solid and generally rectangular in cross section and there is no relationship between forces applied to the lateral edges by the sides of the receiving channel and the forces on the front leading edge and the rear trailing edge of the inserting member.
It is believed to be an improvement to these types of dovetail fittings to shape the inserting member as somewhat conical and to initially provide both side clearance and top-to-bottom clearance. Thus, with such a design as the receiving channel narrows, the inserted member is pushed toward the base surface of the channel. With continued advancement toward the lower end of the channel where the taper narrows, the clamping forces applied to the sides are also transmitted to the leading and trailing edges thus providing four primary contact points, each being approximately 90 degrees apart. The presence of these four points of contact (interference fit) result from the contact made on the two outwardly flared edges of the conical end shape and the contact made on the leading and trailing edges of the inserting member. The described four points of contact, each 90 degrees apart on the inserted member, present an interference force upon the conical shell diameter resulting in a reliable spring-force application. The leading and trailing edges are at a low level relative to the two side portions.
The present invention provides a mounting apparatus consistent with the foregoing description and achieves the advantages and improvements outlined. The apparatus of the present invention also provides additional improvements as will be appreciated from the descriptions which follow.